Tubulous steam generator



Sept. 14 1926. 1,599,726

5 D. v. H. sMiTH TUBULOUS STEAM GENERATOR Filed Oct. 29,- 1921 3 Sheets-$heei 1 w [it Sept. 14 192%.

' D. V. H. SMITH?" TUBULOUS STEAM GENERATOR 3 Sheets-Sheet 2 Filed Oct. 29. 1921 I. lilll'll-llll-I'lllllll-Il II-l. Inlll'nl'|| Patented Sept. 14, 1926.

ETED

DONALD V. H. SMITH, OF GLASGOW, SCOTLAND.

TUBUJhOUS STEAM GENERATOR.

Application filed October 29, 1921, Serial No. 511.397, and in Great. Britain December 8 1920.

This invention has for object improvements in tubular steam generators with capability of having their capacity varied which consist in an arrangement of internal smoke-flues formed by closely disposed staggered diagonal cross-tubes in connection with banked outer tubes for water circulation within the generator said outer tubes and diagonal tubes being connected in separate series, sections or groups to a plurality of top and bottom headers; the top headers being in straight upward communication with a superposed steam drum from which down-circulation is ensured through tubes externally oi the generator-casing. Furthermore, water circulation takes place between the lower sectional headers through horizontal cross-tubes disposed beneath the lire-bars.

With this arrangement I provide two sideflues and an upper return-flue within said casing so that the gases from the fire-hearth below are caused to pass into the side-tines through interstices formed between the lower staggered portions of said diagonal tubes and flow along these flues towards one end oi the casing where a passage is provided by which the flue-gases enter the said return-flue; there being also provided cleaning facilities opposite the junction of tubes in the form of screwed sockets welded on the outer portions of the tubes, and a screwed plug being fitted therein or a cover plate being held in position with studs and nuts, each plate being, if desired, of sufiicient size to cover several openings of crosstubes.

In order to render my invention clear I will describe the same with reference to the annexed drawings, in which Figure 1 is a front elevation, of the generator; Fig. 2, a corresponding side elevation o1 the same; Fig. 3 a vertical crosssection taken on a line 3-3, of Fig. 5; Fig. 4 a vertical cross-section taken on a line 4l--4t, of Fig. 5, but parts beingbroken away; Fig. 5 a central transverse section of the generator-tubes; and Fig. (5 a plan corresponding to Fig. 5. V

The tubulous boiler is provided with an enclosing casing 1 and a superposed steam drum 2 in a usual manner. Elements oi internal heating tubes 3 are joined to top and bottom headers 4, 5 and 6 respectively to form sections to be individually joined from the corresponding topheader to the drum *2 by a connection 7. The heating tubes 3 consist in upright side tubes, inclined upper tubes 3 communicating with the tubing 3 and headers 4t and crossed tribes 3 or .3 the upper parts 3 of these tubes communicate with the tubes 3 and 3 .as shown. The crossed tubes may be arranged as shown in the Figs. 4c and 5, that is to say one reaching further down than the other, alternately so that the flue-gases can passnpward between the vinterstices so formed. Cover 8 and plugs 9 permit of the crossed tubes be ing cleaned. The lower, headers 5 and '6 communicate with each other through lateral tubes 10 and each lower header has a lateral inlet socket 11 to be connected with an external circulating tube12-descending from the steam drum 2. Cleaning plugs such as 18 are provided where necessary.

A feed w-ater device 14: may be connected by a pipe 15 with the drum '2and by a pipe 16 with the lower header for example. Arrows Y indicate the water circulation.

The lateral tubes 10 are provided with supports 17 shown.

According to the end section shown in Fig. i, thestra'ight central tube 18 leads from the top header 4 to the apex g ctthe angular connections or inclined tubes 3 cor responding to the lower portions of the aforementioned crossed tubes; said connections being arranged in staggered positions at their lower portions to form interstices for the passage of ascending gases. In providing the boiler, having crossed tubes 3 3, forming an upper return flue 19, with these modified tubular arrangements at the end, the ascending fire gases enter and flow along the lower flues 20, 21 into the larger lateral flues 22, 23 of said modified end sections from which the flue-gases will be enabled to reach the upper return flue 19 and thence be drawn off in any known manner. The arrows X indicate the direction of flow oi": the flue gases into the lower flues.

It will be understood that for the sake of clearness of illustration the tubes 3* and 3 are shown separated; but in actual construction, they are in, or nearly in contact. Resort may be had to any known expedient for attaining water-tight joints between the tubes and headers, such expedients being well within the range of knowledge and to form rests for tire-bars, not

skill of those engaged in the art of boiler construction and therefore not coming within the scope of this invention. Moreover, and for instance, the ends of the tubes may be slightly reduced in diameter to permit ingress of molten metal between them during the operation of welding without causing separation of the tubes. Further, any small openings between the tubes, which may be occasioned by a thin film of metal entering between the ends when they are not reduced as described above, may be closed by any suitable fillin In operation, the heated gases pass upwardly into the fines 20, 21, through the openings caused by staggering of the tubes 3", 3. Proceeding to the rear of the boiler, the heated products of combustion arrive at the last modified section, (shown in Fig. 4:) the absence of crossing tubes permitting access of the heated gas to the flues 19 and chimney stack. The water, being quickly heated, sets up a circulation indicated by the arrows Y, as hereinbefore described.

I claim:

1. In a tubulous steam generator, a series of substantially axially aligned water and steam circulating components each comprising intersecting and intercommunicating cross tubes, side tubes communicating with said cross tubes and upper inclined tubes also communicating with said cross-tubes, said tubes forming the walls of a pair of lateral smoke lines and an upper return flue, and end components of modified construction merging said lateral fiues and upper return flue, the lower branches of adjacent crossed tubes being staggered to provide smoke passages therebetween as set forth.

2. In a tubulous steam generator, a series of substantially axially aligned water and steam circulating components each comprising intersecting and intercommunicating cross tubes, side tubes communicating with said cross-tubes and upper inclined tubes also communicating with said cross-tubes, said tubes forming the walls of a pair of lateral smoke flues and an upper return flue, the upper branches of the cross tubes being removed in the .end components and replaced by a single tube joining the intersection of the cross tubes with the junction of the upper inclined tubes and the lower branches of all the crossed tubes being displaced alternately, as and for the purpose set forth.

3. A tubulous steam generator consisting of a series of sets of substantially axially aligned water and steam circulating components each comprising intersecting and intercommunicating cross tubes, side tubes communicating with said cross-tubes and upper inclined tubes also communicating with said cross-tubes, said tubes forming the walls of a pair of lateral smoke flues and an upper return flue, the lower branches of adjacent cross tubes being staggered to provide smoke passages therebetween, end components of modified construction merging said lateral flues and upper return flue, an upper header common to the upper inclined tubes in each set, lower headers common to the side tubes in each set, tubes directly connecting said lower headers, and a drum directly connected to the upper and lower headers, as set forth.

DONALD V. H. SMITH. 

